so are you playing these MSN sounds in your yahoo program? what i mean is, does it seem like the yahoo program is making the volume of the sound files diminished, or do you think that the sound files themselves are of a poor quality? if you're unsure, try playing some MSN-or-whatever sound files in the yahoo program, and see if they too sound diminished. then try playing the yahoo sound files in a regular sound-playing program. if the yahoo program is making the sound files sound worse, then you should be able to mess around with the sound settings and increase the volume (i use kopete for my instant messaging needs, so i can't give you specifics on what to click on and where). if the sound files themselves are crappy, you could try increasing their volume with a sound-manipulation program like audacity.